You can strip it down to the metal frame and build whatever kind of sidewall you like, but it's a huge amount of work and expensive as well. Even when DIY. Aluminum sheet metal would be classy, but corrugated aluminum siding is probably less expensive. Or fiberglass sheet (filon) - it doesn't have to be laminated fiberglass walls.
Plus you need to fix whatever caused the delam to being with. Leaky roof seams?
Former owner of 2004 American Tradition and several other RVs
Home is in the Ocala Nat'l Forest near Ocala, FL
Summers in Black Mountain, NC